Genetic Organization in CAENORHABDITIS ELEGANS: Fine-Structure Analysis of the unc-22 Gene.

Fine-structure analysis of the unc-22 gene of Caenorhabditis elegans has revealed a number of sites that are separable by recombination. Eight new ethyl methanesulfonate-induced recessive mutations of the unc-22 gene have been isolated. Using these new alleles, as well as e66, a number of separable sites have been identified and positioned relative to one another. The map distances obtained are found to be comparable to those associated with intragenic recombination in Drosophila melanogaster, indicating that genetic fine-structure analysis is feasible in Caenorhabditis elegans. Evidence of possible gene conversion is presented. A preliminary estimate of the unc-22 gene size is 2.4 x 10(-2) map units.